Scope
This BESS project includes ASEC’s detailed engineering services for the design and implementation of a 230 kV Generation Tie transmission line. The Gen-Tie line spans approximately one mile, two-thirds of which is underground. The project involves the interconnection of the Battery Energy Storage System (BESS) with the utility’s substation. The deliverables provided by ASEC include the design of underground line layouts, PLS-CADD models, load trees, plan and profile drawings, and structure configurations. Additionally, ASEC developed design guides, including foundation design and grounding system details.
Technical Challenges
- Constrained Right-of-Way: The underground segment of the transmission line runs adjacent to the utility’s right-of-way, requiring precise coordination to avoid conflicts with existing infrastructure.
- Long Span Design: The overhead portion of the line crosses a train yard and a major water channel, necessitating transmission poles that reach heights of 150-170 feet to achieve the required clearance.
- Seismic Considerations: The project site features liquefiable soils, which required advanced geotechnical analysis and custom foundation designs to meet seismic safety requirements, especially for the substation interconnection.
Value Added Engineering
ASEC optimized the Gen-Tie design by integrating load management strategies and implementing a comprehensive seismic design to withstand ground liquefaction risks. This included seismic foundation analysis and coordination with the substation team to balance pole height and structural loads, reducing the complexity of the design while maintaining stability. During the bid phase, ASEC provided preliminary modeling and estimation to assist in securing the project contract.
